1. Field of the Invention
The present invention relates to electronic locking mechanisms and, in particular, concerns an electronic proximity sensor used to validate locking mechanisms and a tracking system used to determine the times the lock was engaged or disengaged and the times that a door was opened or closed.
2. Description of the Related Art
Boxes and cabinets used in emergency vehicles contain drugs, and these boxes and cabinets have mechanical locking mechanisms in place that are intended to prevent people from accessing those drugs. However, it is easy to pretend to close the lock on these boxes and cabinets while having the door still open, for example by flipping the bayonet of the locking device over to allow the box and/or cabinet to appear locked when it is not.
In the normal construction of a locked box or cabinet, the assumption is that when the lock is engaged the box or cabinet is actually locked. However, mechanical gears can be easily manipulated to fool the box or cabinet to think the bolt is engaged while the door is open. Thus, any sensors that are based on the position of mechanical locking mechanisms can also be fooled. In other words, when using only mechanical locking mechanisms, it is possible to have the bolt extended but for the box or cabinet to not be really locked. For applications where the contents of the box or cabinet need to be absolutely secured, mechanical locking gears are not sufficient.
However, many secure boxes and cabinets comprise metal, and proximity sensors that communicate electromagnetically, such as through induction, do not operate well or at all with a box or cabinet that comprises metal since the metal absorbs the electromagnetic energy. Furthermore, a proximity sensor that detects metal can be easily fooled by positioning metal nearby. Thus, there is a need for a locking validation mechanism that can confirm that the mechanical locking is indeed effective, such as by verifying that a door is closed and that a lock is engaged, and that can operate in an environment where it is substantially surrounded by metal.
Also, medical personnel must access the drugs contained in a box or cabinet during the course of duty to administer the drugs to a patient in need. Therefore, these medical personnel must have the ability to unlock the box or cabinet. However, once these medical personnel have the ability to access the drugs they may remove more of the drugs than is necessary for legitimate treatment of patients. For example, when responding to an emergency call an emergency medical technician may engage in an authorized access of the drugs in the box or cabinet but may remove more drugs than are needed to treat a victim and later engage in unauthorized use of the extra drugs. Or a health care employee with access to the cabinet may unlock the cabinet when no other people are nearby and remove some of the drugs for unauthorized purposes.
Therefore there is a need for a device that facilitates the auditing of any access made to the contents of a box or cabinet. Such a device would advantageously help determine who unlocked/opened the box or cabinet. Consequently, the device would help reduce unauthorized use of the contents of the box or cabinet, which would further reduce the costs of the supplier of the contents, for example by reducing the costs of stocking the box or cabinet with pharmaceuticals. The device would also help reduce the risk of injury to users who may be engaging in unauthorized use of the contents by impairing the access of such users to the contents.